Most of those who've said they've exchanged in via II (vs. a direct exchange with a private owner) have said that they've used a very strong week (primetime at a very high demand, 5 star property), requested far in advance, gave all DVC WDW properties in their search request, gave a very flexible range of several months (like May through October - including time periods when most kids are in school) and were confirmed (into OKW Resort) under 7 months ahead, sometimes only 2-4 months ahead. Most seemed to accept 1BRs with 2BRs much less commonly. It's probably best to have a back-up plan and assume that you are going to be one of those who do not get a match.
OTOH, if you:
--- plan to travel in May/early June or late August/September
--- have a very strong trader
--- can accept anything from a studio to a 2BR
then, see what happens!
It's usually pretty easy to get a decent exchange into another non-DVC resort in the area during those times, if you have to expand your search request to include them, say, 3 months ahead. JMHO. Wish you well!